In the technology of semiconductor fabrication it is well known to expose a layer of photoresist on a semiconductor wafer to a pattern of radiation, a process referred to as photolithography. The unexposed portions of the photoresist are removed by a developer solution, and the resulting photoresist pattern is used in processing the wafer. Usually the photoresist is exposed by directing the radiation through a photomask. Using ultraviolet light, these techniques can depict features having dimensions as small as approximately 0.5 .mu.m. Photolithography systems which use x-ray technology can achieve higher resolution, but these systems are generally quite large and expensive.
Hence, there is a need for a photolithography system that can produce extremely small features (as small as, say, 0.1 .mu.m) and yet avoid the size and cost of x-ray systems. A system using an excimer laser beam guided through a hollow glass pipette is proposed in M. Rudman et al., "Near-field subwavelength micropattern generation: Pipette guided argon fluoride excimer laser microfabrication", J. Appl. Phys., Vol. 72, 1 Nov. 1992, pp. 4379-4383, which is incorporated herein by reference.